Moreover, PD‐1+, PD‐L2+, ICOS+, T‐cell immunoglobulin mucin‐3 (Tim‐3)+ and lymphocyte activating 3 (LAG‐3)+ CD8 T cells were significantly increased in the BM of MM patients (Figure 3e and Supplementary figure 4b). Here, ICOS is linked to Miyoshi myopathy.